Antenna module, communication device equipped with the same, and manufacturing method of antenna module

ABSTRACT

An antenna module includes a dielectric substrate and a radiation element disposed on the dielectric substrate. The dielectric substrate includes a flat portion (131) and a flat portion (130) having mutually different normal directions, and a bent portion connecting the flat portion (131) and the flat portion (130) to each other. The flat portion (131) has a protruding portion partially protruding in a direction toward the flat portion (130) along the flat portion (131) from a boundary portion between the bent portion and the flat portion (131). The flat portion (131) and the bent portion are connected to each other at a position where the protruding portion is not provided in the flat portion (131). At least a part of the radiation element is disposed on the protruding portion.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of U.S. application Ser. No. 17/021,069 filed onSep. 15, 2020, which is a continuation of International Application No.PCT/JP2020/002731 filed on Jan. 27, 2020 which claims priority fromJapanese Patent Application No. 2019-027976 filed on Feb. 20, 2019 andJapanese Patent Application No. 2019-190354 filed on Oct. 17, 2019. Thecontents of these applications are incorporated herein by reference intheir entireties.

BACKGROUND Technical Field

The present disclosure relates to an antenna module and a communicationdevice equipped with the same, and a manufacturing method of an antennamodule, and more specifically, relates to a technique for miniaturizingan antenna module.

As an antenna element (radiation element) of a mobile terminal(communication device), such as a smartphone, a patch antenna having aflat plate shape may be used in some cases. Since radio waves radiatedby the patch antenna have high directivity (rectilinear propagationcharacteristics), in order to radiate radio waves in many directions, itis suitable to arrange the antennas along respective surfaces of ahousing of the mobile terminal.

Japanese Patent No. 6168258 (Patent Document 1) discloses aconfiguration in which, in an antenna module including a multilayersubstrate including a rigid portion in which a radiation element isdisposed and a flexible portion in which a transmission line is formedand that has flexibility, the rigid portion is bent with respect to anextending direction of the transmission line. By employing an antennamodule in which a radiation element is disposed in such a flexiblemultilayer substrate, it is possible to easily incorporate the antennamodule into a limited space in a housing.

-   Patent Document 1: Japanese Patent No. 6168258

BRIEF SUMMARY

Mobile terminals are required to be further miniaturized and thinned, sothat antenna modules to be used for the mobile terminals are required tobe further miniaturized.

On the other hand, in order to miniaturize the antenna module, when aneffective area of an antenna element or a thickness of a dielectriclayer of an antenna is reduced, there is a concern that antennacharacteristics deteriorate.

The present disclosure provides a miniaturized antenna module that canbe disposed in a limited space in a communication device whilesuppressing a reduction in antenna characteristics.

An antenna module according to an aspect of the present disclosureincludes a dielectric substrate and a first radiation element disposedon the dielectric substrate. The dielectric substrate includes a firstflat portion and a second flat portion having mutually different normaldirections, and a first bent portion connecting the first flat portionand the second flat portion. The first flat portion has a firstprotruding portion partially protruding in a direction toward the secondflat portion along the first flat portion from a boundary portionbetween the first bent portion and the first flat portion. The firstflat portion and the first bent portion are connected to each other at aposition where the first protruding portion is not provided in the firstflat portion. At least a part of the first radiation element is disposedon the first protruding portion.

A manufacturing method of an antenna module according to another aspectof the present disclosure includes a first step of forming a slit havinga substantially C-shape and penetrating in a thickness direction of adielectric substrate. The substantially C-shape can include a U-shapethat has two corners in the closed end. The slit has a first portion anda second portion facing each other, and a third portion connecting anend portion of the first portion and an end portion of the secondportion. The manufacturing method further includes a second step ofbending the dielectric substrate in the first portion and the secondportion of the slit, and forming a first flat portion, a second flatportion, and a bent portion connecting the first flat portion and thesecond flat portion in the dielectric substrate. The second stepincludes steps of forming, in the first flat portion, a protrudingportion partially protruding in a direction toward the second flatportion along the first flat portion from a boundary portion between thebent portion and the first flat portion by forming the bent portion, anddisposing at least a part of a radiation element on the protrudingportion.

According to the antenna module of the present disclosure, at least thepart of the radiation element is disposed on the protruding portion ofthe first flat portion formed by bending the dielectric substrate. Thismakes it possible to dispose the radiation element in a dead spaceportion that is generated in a communication device. Further, since thefirst flat portion and the second flat portion of the dielectricsubstrate are connected to each other by the bent portion in a portionwhere the protruding portion is not formed, a thickness of thedielectric substrate in the protruding portion is maintained in theoriginal thickness of the dielectric substrate. This makes it possibleto suppress a decrease in antenna characteristics due to a reduction inthickness of the dielectric layer. Therefore, according to the antennamodule of the present disclosure, it is possible to provide aminiaturized antenna module that can be disposed in a limited space in acommunication device while suppressing a decrease in antennacharacteristics.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a block diagram of a communication device to which an antennamodule according to Embodiment 1 is applied.

FIG. 2 is a perspective view of the antenna module according toEmbodiment 1.

FIG. 3 is a cross-sectional view of the antenna module according toEmbodiment 1.

FIG. 4 is a cross-sectional view when the antenna module in FIG. 3 isincorporated in a housing.

FIG. 5 is a cross-sectional view of an antenna module according to acomparative example.

FIG. 6 is a diagram for describing a path of a power supply wiring inthe antenna module according to Embodiment 1.

FIGS. 7A, 7B, 7C, and 7D are diagrams illustrating an overview of amanufacturing method of the antenna module according to Embodiment 1.

FIG. 8 is a diagram illustrating a first example of a slit shape.

FIGS. 9A and 9B are diagram for describing a slit forming method.

FIG. 10 is a diagram illustrating a second example of a slit shape.

FIG. 11 is a diagram illustrating a third example of a slit shape.

FIG. 12 is a perspective view of an antenna module according toModification 1.

FIG. 13 is a perspective view of an antenna module according toModification 2.

FIG. 14 is a cross-sectional view of an antenna module according toModification 3.

FIG. 15 is a cross-sectional view of an antenna module according toModification 4.

FIG. 16 is a perspective view of an antenna module according toModification 5.

FIG. 17 is a perspective view of an antenna module according toModification 6.

FIG. 18 is a perspective view of an antenna module according toEmbodiment 2.

FIG. 19 is a diagram for describing a slit shape to be formed in amanufacturing process of the antenna module in FIG. 18 .

FIG. 20 is a perspective view of an antenna module according toEmbodiment 3.

FIG. 21 is a diagram for describing a slit shape to be formed in amanufacturing process of the antenna module in FIG. 20 .

FIG. 22 is a perspective view of an antenna module according toEmbodiment 4.

FIG. 23 is a diagram for describing a slit shape to be formed in amanufacturing process of the antenna module in FIG. 22 .

FIG. 24 is a perspective view of an antenna module according toEmbodiment 5.

FIG. 25 is a diagram for describing radiation directions of radio waveswhen the antenna modules in FIG. 24 are mounted on a housing.

FIG. 26 is a perspective view of a modification of the antenna moduleaccording to Embodiment 5.

FIG. 27 is a perspective view of an antenna module according toEmbodiment 6.

FIG. 28 is a cross-sectional view of a first example of an antennamodule according to Embodiment 7.

FIG. 29 is a cross-sectional view of a second example of the antennamodule according to Embodiment 7.

FIG. 30 is a cross-sectional view of an antenna module according toEmbodiment 8.

FIG. 31 is a cross-sectional view of an antenna module according toEmbodiment 9.

FIG. 32 is a perspective view of an antenna module according toEmbodiment 10.

FIG. 33 is a cross-sectional view of the antenna module in FIG. 32 .

FIG. 34 is a cross-sectional view of a first modification of the antennamodule in FIG. 32 .

FIG. 35 is a cross-sectional view of a second modification of theantenna module in FIG. 32 .

FIG. 36 is a perspective view of an antenna module according toEmbodiment 11.

FIG. 37 is a cross-sectional view of a first example of an antennamodule according to Embodiment 12.

FIG. 38 is a cross-sectional view of a second example of the antennamodule according to Embodiment 12.

FIG. 39 is a cross-sectional view of a first example of an antennamodule according to Embodiment 13.

FIG. 40 is a cross-sectional view of a second example of the antennamodule according to Embodiment 13.

FIG. 41 is a cross-sectional view of a first example of an antennamodule according to Embodiment 14.

FIG. 42 is a cross-sectional view of a second example of the antennamodule according to Embodiment 14.

FIG. 43 is a perspective view of an antenna module according toEmbodiment 15.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure will be described indetail with reference to the drawings. Note that the same orcorresponding parts in the drawings are denoted by the same referencesigns, and description thereof will not be repeated.

Embodiment 1

(Basic Configuration of Communication Device)

FIG. 1 is an example of a block diagram of a communication device 10 towhich an antenna module 100 according to Embodiment 1 is applied. Thecommunication device 10 is, for example, a mobile terminal, such as amobile phone, a smartphone, or a tablet, a personal computer having acommunication function, or the like. Examples of a frequency band ofradio waves to be used in the antenna module 100 according to thepresent embodiment include radio waves in a millimeter wave band having,for example, 28 GHz, 39 GHz, and 60 GHz as center frequencies, but radiowaves in a frequency band other than those described above are alsoapplicable.

With reference to FIG. 1 , the communication device 10 includes theantenna module 100 and a BBIC 200 configuring a baseband signalprocessing circuit. The antenna module 100 includes an RFIC 110 which isan example of a power supply circuit, and an antenna device 120. Thecommunication device 10 up-converts a signal transmitted from the BBIC200 to the antenna module 100 into a radio frequency signal to radiatethe radio frequency signal from the antenna device 120, anddown-converts a radio frequency signal received by the antenna device120 to process the down-converted signal in the BBIC 200.

In FIG. 1 , for ease of description, only a configuration correspondingto four power supply elements 121 among a plurality of power supplyelements 121 included in the antenna device 120 is illustrated, andconfigurations corresponding to the other power supply elements 121having the same configuration are omitted. Note that FIG. 1 illustratesan example in which the antenna device 120 is formed by using theplurality of power supply elements 121 arranged in a two-dimensionalarray, but the plurality of the power supply elements 121 is notnecessarily provided, and the antenna device 120 may be formed by usinga single power supply element 121. In addition, the plurality of powersupply elements 121 may be arranged in a row as a one-dimensional array.In the present embodiment, the power supply element 121 is a patchantenna having a substantially square flat plate shape.

The RFIC 110 includes switches 111A to 111D, 113A to 113D, and 117,power amplifiers 112AT to 112DT, low-noise amplifiers 112AR to 112DR,attenuators 114A to 114D, phase shifters 115A to 115D, a signalmultiplexer/demultiplexer 116, a mixer 118, and an amplification circuit119.

When a radio frequency signal is transmitted, the switches 111A to 111Dand 113A to 113D are switched to sides of the power amplifiers 112 AT to112 DT, and the switch 117 is connected to a transmission-side amplifierof the amplification circuit 119. When a radio frequency signal isreceived, the switches 111A to 111D and 113A to 113D are switched tosides of the low-noise amplifiers 112 AR to 112 DR, and the switch 117is connected to a reception-side amplifier of the amplification circuit119.

A signal transmitted from the BBIC 200 is amplified by the amplificationcircuit 119, and is up-converted by the mixer 118. A transmission signalwhich is the up-converted radio frequency signal is demultiplexed intofour demultiplexed signals by the signal multiplexer/demultiplexer 116,and the four demultiplexed signals pass through four signal paths, andare individually supplied to the different power supply elements 121. Atthis time, directivity of the antenna device 120 can be adjusted byindividually adjusting phase shift degrees of the phase shifters 115A to115D arranged in the respective signal paths.

Reception signals which are radio frequency signals received by therespective power supply elements 121 individually pass through the fourdifferent signal paths and are multiplexed by the signalmultiplexer/demultiplexer 116. The multiplexed reception signal isdown-converted by the mixer 118, amplified by the amplification circuit119, and transmitted to the BBIC 200.

The RFIC 110 is formed as, for example, a one-chip integrated circuitcomponent including the above-described circuit configuration.Alternatively, devices (switches, power amplifiers, low-noiseamplifiers, attenuators, and phase shifters) corresponding to therespective power supply elements 121 in the RFIC 110 may be formed asone-chip integrated circuit component for each of the correspondingpower supply elements 121.

(Configuration of Antenna Module)

Next, the configuration of the antenna module 100 according toEmbodiment 1 will be described in detail with reference to FIG. 2 andFIG. 3 . FIG. 2 is a perspective view of the antenna module 100.Additionally, FIG. 3 is a cross-sectional view of the antenna module 100in a state in which the antenna module 100 is mounted on a mountingsubstrate 20.

With reference to FIG. 2 and FIG. 3 , the antenna module 100 includes,in addition to the power supply elements 121 and the RFIC 110, adielectric substrate 105, power supply wirings 170 and 171, and a groundelectrode GND. Note that, in the following description, a positivedirection of a Z-axis in each figure may be referred to as an uppersurface side, and a negative direction may be referred to as a lowersurface side in some cases.

The dielectric substrate 105 is, for example, a low temperature co-firedceramic (LTCC) multilayer substrate, a multilayer resin substrate formedby laminating a plurality of resin layers formed of resin, such asepoxy, polyimide, or the like, a multilayer resin substrate formed bylaminating a plurality of resin layers formed of liquid crystal polymer(LCP) having a lower dielectric constant, a multilayer resin substrateformed by laminating a plurality of resin layers formed of fluororesin,or a ceramic multilayer substrate other than LTCC. Note that thedielectric substrate 105 need not be a multilayer structure, and may bea single-layer substrate.

In the antenna device 120 of the antenna module 100, the dielectricsubstrate 105 has a substantially L-shaped cross-sectional shape, andincludes a flat portion 130 with a Z-axis direction in FIG. 2 and FIG. 3being as a normal direction, a flat portion 131 with an X-axis directionin FIG. 2 and FIG. 3 being as a normal direction, and a bent portion 135connecting the two flat portions 130 and 131. Note that, in Embodiment1, the flat portion 131 corresponds to the “first flat portion” of thepresent disclosure, and the flat portion 130 corresponds to the “secondflat portion” of the present disclosure.

In the antenna module 100, four power supply elements 121 are arrangedin a row in a Y-axis direction on each of the two flat portions 130 and131. In the following description, for ease of understanding, an examplein which the power supply elements 121 are arranged so as to be exposedon surfaces of the flat portions 130 and 131 will be described, but thepower supply elements 121 may be arranged inside the dielectricsubstrate of the flat portions 130 and 131.

The flat portion 130 has a substantially rectangular shape, and fourpower supply elements 121 are arranged in a row on a surface of the flatportion 130. Further, the RFIC 110 is connected to a lower surface side(a surface in the negative direction of the Z-axis) of the flat portion130. The RFIC 110 is mounted on a surface 21 of the mounting substrate20 with solder bumps 140 interposed therebetween. Note that the RFIC 110may be mounted on the mounting substrate 20 by using a multipolarconnector instead of solder connection.

The flat portion 131 is connected to the bent portion 135 bent from theflat portion 130, and is disposed such that a surface of an inner sideportion (a surface in a negative direction of the X-axis) of the flatportion 131 faces a side surface 22 of the mounting substrate 20. Theflat portion 131 has a configuration in which a plurality of cutoutportions 136 is formed in the dielectric substrate having asubstantially rectangular shape, and the bent portion 135 is connectedto the cutout portions 136. In other words, in a portion of the flatportion 131 where the cutout portion 136 is not formed, protrudingportions 133 protruding in a direction toward the flat portion 130 (thatis, in the positive direction of the Z-axis) along the flat portion 131from a boundary portion 134 to which the bent portion 135 and the flatportion 131 are connected are formed. A protruding end of the protrudingportion 133 is positioned in the positive direction of the Z-axis withrespect to the surface on the lower surface side of the flat portion 130(on the side facing the mounting substrate 20). Note that, in Embodiment1, a surface on an upper surface side of the flat portion 130 (a surfacepositioned in an outer side portion) corresponds to a “first surface” ofthe present disclosure, and the surface on the lower surface side of theflat portion 130 (the surface facing the mounting substrate 20)corresponds to a “second surface” of the present disclosure. Further, inEmbodiment 1, the bent portion 135 corresponds to the “first bentportion” of the present disclosure.

In the antenna module 100 in FIG. 2 , four protruding portions 133 areformed corresponding to the four power supply elements 121 arranged onthe flat portion 130. In addition, one power supply element 121 isarranged for each of the protruding portions 133. Each power supplyelement 121 in the flat portion 131 is arranged such that at least apart thereof overlaps with the protruding portion 133.

Note that, in Embodiment 1, one of the protruding portions 133 formed inthe flat portion 131 corresponds to the “first protruding portion” ofthe present disclosure, and the other protruding portions 133 correspondto a “second protruding portion” of the present disclosure. In addition,in Embodiment 1, one of the power supply elements 121 arranged on theflat portion 131 corresponds to the “first radiation element” of thepresent disclosure, and the other power supply elements 121 arranged onthe flat portion 131 correspond to a “second radiation element” of thepresent disclosure. In Embodiment 1, each of the power supply elements121 arranged on the flat portion 130 corresponds to a “third radiationelement” of the present disclosure.

The ground electrode GND is disposed on a surface facing the mountingsubstrate 20 or an inner layer of the flat portions 130 and 131 and thebent portion 135. A radio frequency signal from the RFIC 110 istransmitted to the power supply element 121 on the flat portion 130through the power supply wiring 170. Further, a radio frequency signalfrom the RFIC 110 is transmitted to the power supply element 121 on theflat portion 131 through the power supply wiring 171. The power supplywiring 171 is connected to the power supply element 121 arranged on theflat portion 131 through an inside of each dielectric substrate of theflat portions 130 and 131 and an inside (or a surface) of the dielectricsubstrate of the bent portion 135 from the RFIC 110.

As will be described later in FIGS. 7A-7D, the flat portions 130 and 131and the bent portion 135 are formed by partially processing and bendingthe dielectric substrate 105 having a flat plate shape. At this time, athickness of the flat portion 131, including a portion of the protrudingportion 133, is the same as a thickness of the flat portion 130.Accordingly, it is possible to suppress a decrease in antennacharacteristics due to a decrease in thickness of the dielectricsubstrate for the power supply elements 121 on the flat portion 131.

FIG. 4 is a cross-sectional view of the antenna module 100 in a state inwhich the antenna module 100 is incorporated inside a housing 30 of thecommunication device 10. The antenna module 100 is arranged so as toface an inner side portion of two adjacent surfaces of the housing 30.In the example of FIG. 4 , the housing 30 is formed of a dielectricmaterial, such as resin or glass, and the power supply elements 121 aredisposed so as to be in contact with the housing 30. Note that, when thepower supply element 121 is disposed on an inner layer, the dielectricsubstrate (the flat portions 130 and 131) is disposed so as to be incontact with the housing 30. In addition, when the housing 30 is formedof a metal material, the housing 30 itself acts as a shield for blockingradio waves, so that a portion where the power supply element 121 facesis partially provided with a dielectric material.

FIG. 5 is a cross-sectional view of an antenna module 100 # according toa comparative example in a state in which the antenna module 100 # isincorporated in an inside of the housing 30. Unlike the flat portion 131in the antenna module 100, a flat portion 131 # in the antenna module100 # according to the comparative example does not protrude from a bentportion 135 #, and is disposed so as to further extend from an endportion of the bent portion 135 #. In the configuration, such as theantenna module 100 #, a region AR1 on an inner side portion of a cornerportion of the housing 30 illustrated in FIG. 5 cannot be effectivelyutilized, and a dimension of the antenna module 100 # in a Z-axisdirection is larger than a dimension of the antenna module 100 in theZ-axis direction in Embodiment 1.

In recent years, demands for miniaturizing and thinning of communicationdevices have been further increased, but when the dimension in theZ-axis direction is shortened in the structure, such as the antennamodule 100 # according to the comparative example, it is suitable toreduce a size of the power supply element 121 arranged on the flatportion 131 #, and thus desired antenna characteristics may not beobtained.

On the other hand, as in Embodiment 1, by adopting the structure inwhich the flat portion 131 protrudes in the direction toward the flatportion 130 with respect to the bent portion 135, it is possible todispose the power supply element 121 in the region AR1 illustrated inFIG. 5 . Accordingly, it is possible to reduce the dimension of theentire antenna module in the Z-axis direction while maintaining the sizeof the power supply element 121. Therefore, it is possible to provide aminiaturized antenna module that can be disposed in a limited space in acommunication device while suppressing a reduction in antennacharacteristics.

Note that, as described above, in the antenna module 100 according toEmbodiment 1, a thickness of the dielectric substrate in the protrudingportion 133 is the same as a thickness of the dielectric substrate inthe other portion of the flat portion 131. Therefore, it is possible tosuppress a decrease in antenna characteristics due to a decrease inthickness of the dielectric substrate.

FIG. 6 is a diagram for describing a path of the power supply wiring 171that transmits a radio frequency signal to the power supply element 121on the flat portion 131. With reference to FIG. 6 , the power supplywiring 171 passes through an inside of the dielectric substrate of theflat portion 130 from the RFIC 110, and reaches the flat portion 131through the bent portion 135. In the flat portion 131, the power supplywiring 171 further extends to a position in the negative direction ofthe Z-axis with respect to the boundary portion 134 between the bentportion 135 and the flat portion 131, and is bent in the Y-axisdirection from the position to be connected to the power supply element121.

At this time, when the boundary portion 134 is positioned in thenegative direction of the Z-axis with respect to a power supply point SPof the power supply element 121, a length of the power supply wiring 171from the RFIC 110 to the power supply element 121 increases, and a lossin the power supply wiring 171 slightly increases, but since a curvatureradius of the bent portion 135 can be made large, it is possible toreduce stress to be applied to the bent portion 135 and to suppress adamage to the bent portion 135. Further, since a protruding amount ofthe protruding portion 133 can be increased, the protruding end of theprotruding portion 133 can be disposed at a higher position, and adegree of freedom in arrangement in the housing 30 can be increased.

On the other hand, when the boundary portion 134 is positioned in thepositive direction of the Z-axis with respect to the power supply pointSP of the power supply element 121, the length of the power supplywiring 171 can be shortened, and therefore, the loss in the power supplywiring 171 can be suppressed, but the bending processing of the flatportion 131 is less likely to be performed. The position of the boundaryportion 134, that is, the protruding amount of the protruding portion133 is appropriately set depending on an acceptable loss and thearrangement of the power supply elements 121 on the flat portion 131.

(Manufacturing Process)

Next, a manufacturing process of the antenna module 100 will bedescribed with reference to FIGS. 7A-7D. The processes proceed from FIG.7A to FIG. 7D. In each process, a plan view when the antenna module 100is viewed from a normal direction (that is, the Z-axis direction) of thedielectric substrate 105 is illustrated in an upper row, and across-sectional view including a portion where the bent portion 135 isformed is illustrated in a lower row. Note that, in the cross-sectionalview, for ease of description, a ground electrode, a power supplywiring, and a wiring pattern in the dielectric substrate are omitted.

First, in a process illustrated in FIG. 7A, the dielectric substrate 105is formed by laminating a plurality of dielectric layers each of which adielectric and a metal film formed in a desired pattern are bonded toeach other. A ground electrode, the power supply element 121, and thelike are formed by the metal film of each dielectric layer. At thistime, an electrode 190 having the same shape as that of the bent portion135 is formed in an inner layer of a portion of the dielectric substrate105 that serves as the flat portion 131.

Next, in a process illustrated in FIG. 7B, the dielectric in the portionwhere the bent portion 135 is formed is removed by laser processing, anda concave portion 195 is formed in the dielectric substrate 105. At thistime, only the dielectric in an upper portion than the electrode 190described above is removed by the laser. That is, the electrode 190functions as a guard electrode for blocking the laser when the laserprocessing is performed. As a result, when the dielectric substrate 105is seen in a plan view, the electrode 190 is exposed. With the electrode190, a desired thickness of the bent portion 135 is ensured. Note thatthe power supply wiring 171 reaching the flat portion 131 is formed in alayer on the lower surface side than the electrode 190.

A slit 150 which penetrates the dielectric substrate 105 in thethickness direction is formed by the laser processing at a boundaryportion between a portion to be the protruding portion 133 and a portionto be the bent portion 135. Note that the electrode 190 is not formed ata portion where the slit 150 is formed.

In the above-described process of FIG. 7B, an order of the process offorming the slit 150 and the process of forming the concave portion 195is not particularly limited. That is, the concave portion 195 may beformed before the slit 150 is formed, or the concave portion may beformed after the slit 150 is formed. Note that, in the laser processingin forming the slit 150, dirt may adhere to the surrounding dielectricdue to smear (soot) generated during the processing. Therefore, byforming the concave portion 195 after forming the slit 150, it ispossible to remove the dielectric to which the dirt adheres in formingthe concave portion 195, and it is possible to suppress an appearancedefect in a final product.

Thereafter, in a process illustrated in FIG. 7C, the exposed electrode190 is removed by performing etching processing. Note that, in a casewhere the power supply element 121 is disposed on the surface of thedielectric substrate 105, mask processing is applied to a portion of thepower supply element 121 by using resist or the like before the etchingprocessing.

Then, in a process illustrated in FIG. 7D, the dielectric substrate 105is bent along the Y-axis at a portion of the bent portion 135. As aresult, a normal line of the flat portion 131 is directed in the X-axisdirection. At this time, since the slit 150 is formed, a part of thedielectric substrate rises from a surface of the bent portion 135, theprotruding portion 133 is formed, and at least a part of the powersupply element 121 is disposed on the protruding portion 133. Thereby,the antenna device 120 is formed. Thereafter, the RFIC 110 is connectedto a lower surface side of the flat portion 130, so that the antennamodule 100 is formed.

Note that the removal of the dielectric may be performed by a processingmethod (for example, router processing) other than the laser processing.In this case, the electrode 190 that functions as the guard electrode isnot required.

(Slit Shape)

In the bending process of FIG. 7D, it is desirable to bend thedielectric substrate 105 in a straight line along the Y-axis throughoutthe entire dielectric substrate 105. When a portion where stressconcentration occurs (stress concentration point) exists in the slit 150when the dielectric substrate 105 is bent, the dielectric substrate 105is easily bent at the stress concentration point. Therefore, the slit150 can have a shape in which the stress concentration is generated asmuch as possible in a portion to be bent, and in contrast, the stressconcentration does not occur in a portion that is not required to bebent.

FIG. 8 is a diagram illustrating a first example of a slit shape. Asillustrated in FIG. 8 , the slit 150 has an angular C-shape as a whole.Here, it is generally known that stress is likely to concentrate in anangular portion. Therefore, by forming corner portions 155 at which twoslits (a first portion, a second portion) extending in the X-axisdirection and facing each other and a slit (a third portion) extendingin the Y-axis direction intersect each other in a circular arc shapehaving a predetermined curvature radius, stress concentration at thecorner portions 155 can be reduced. Thereby, it is possible to suppressbending at the third portion of the slit 150 along the Y-axis direction.However, an inner side portion of the slit 150, that is, a cornerportion having a convex shape at an end portion of the protrudingportion 133 on which the power supply element 121 is disposed, can be inan angular shape in order to ensure an area of the ground electrode GNDas large as possible.

In a case where the slit 150 is formed by the laser processing, when thelaser is irradiated in a path returning from a start point ST along aboundary between the slit 150 and the dielectric substrate to the startpoint ST as illustrated in FIG. 9A, the corner portion having the convexshape of the end portion of the protruding portion 133 has a curved linehaving no small curvature. Further, when an end point of the processingdoes not coincide with the start point ST, the dielectric in a portionof the slit 150 is not removed, which may cause a processing defect.

Therefore, as illustrated in FIG. 9B, the slit 150 can be formed by twoprocesses. In a first process, the processing starts from a start pointST1 on an extension of the end portion along the X-axis of theprotruding portion 133, the laser is irradiated along the boundarybetween the slit 150 and the dielectric substrate, and the irradiationof the laser is once ended at an end point ED1 on an extension line ofthe other end portion along the X-axis of the protruding portion 133.Then, in a second process, the irradiation of the laser is resumed froma start point ST2 on an extension of the end portion along the Y-axis ofthe protruding portion 133, and the laser is irradiated along the Y-axisto an end point ED2 on an extension of the other end portion along theY-axis of the protruding portion 133.

By forming the slit 150 in such a process, it is possible to reduce thestress concentration by forming a corner portion having a concave shapeof the substrate in a circular arc shape, and to secure the area of theground electrode GND by forming a corner portion having a convex shapein an angular shape. Further, by making a start point and an end pointof the irradiation of the laser different from each other, it ispossible to suppress a processing defect in which a dielectric is notremoved.

FIG. 10 and FIG. 11 illustrate other examples of a slit shape. In eachof a second example illustrated in FIG. 10 and a third exampleillustrated in FIG. 11 , an example of a slit shape for bending thedielectric substrate 105 at a desired position is illustrated.

In a slit 150A of the second example in FIG. 10 , a shape of a side ofan outer side portion in each of slits (a first portion 150A1, a secondportion 150A2) formed along the X-axis direction is formed in a circulararc shape, and a slit opening width gradually increases toward a centralportion in the X-axis direction of the first portion 150A1 and thesecond portion 150A2. As a result, a portion of the bent portion 135whose dimension (width) in the Y-axis direction is smaller than that inan end portion of the slit exists. In the example of FIG. 10 , a widthW2 of the bent portion 135 in a portion along a virtual line CL1 is theminimum width of the bent portion 135. Therefore, when the dielectricsubstrate 105 is bent, stress tends to concentrate on the portion wherethe width of the bent portion 135 is minimum, and as a result, the bentportion 135 bends along the virtual line CL1.

In a slit 150B of the third example of FIG. 11 , in each of slits (afirst portion 150B1 and a second portion 150B2) formed along the X-axisdirection, a concave portion 152 is formed along a virtual line CL2 suchthat an opening portion of the slit is wider than that of both endportions of the slit. Accordingly, since a width of the bent portion 135in a portion where the concave portion 152 is formed is minimum, whenthe dielectric substrate 105 is bent, stress tends to concentrate on theportion where the concave portion 152 is formed, and the bent portion135 bends along the virtual line CL2.

As described above, the bending position can be adjusted by contrivingthe slit shape.

(Modifications)

Hereinafter, variations (modifications) of the antenna module will bedescribed.

(Modifications of Cutout Portion: Modification 1, Modification 2)

In the antenna module 100 according to Embodiment 1, the example hasbeen described in which the cutout portions 136 are formed between allthe power supply elements 121 adjacent to each other on the flat portion131, but it is optional to form the cutout portions 136 between all thepower supply elements 121 adjacent to each other.

FIG. 12 is a perspective view illustrating an antenna module 100Aaccording to Modification 1. In an antenna device 120A of the antennamodule 100A, the cutout portion 136 is provided only between two powersupply elements 121 in a central portion among four power supplyelements 121, and the bent portion 135 is formed at positions of thecutout portion 136 and both end portions in the Y-axis direction of theflat portion 131. That is, in the antenna module 100A, two power supplyelements 121 are formed in each of two protruding portions 133A.

In addition, in an antenna device 120B of an antenna module 100Baccording to Modification 2 in FIG. 13 , the cutout portions 136 areformed between first and second power supply elements 121 and betweenthird and fourth power supply elements 121 among four power supplyelements 121, and the bent portion 135 is formed at positions of thecutout portions 136. That is, in the antenna module 100B, one powersupply element 121 is arranged in each of protruding portions 133B atboth end portions of the flat portion 131, and two power supply elements121 are arranged in a protruding portion 133C in a central portion.

The antenna module 100A according to Modification 1 and the antennamodule 100B according to Modification 2 differ from each other in sizeand shape of the dielectric substrate 105 and the ground electrode GNDin the flat portion 131, as compared with the antenna module 100, due toa difference in position at which the cutout portion 136 is formed. Asdescribed above, when the dielectric substrate 105 and the groundelectrode GND are different from each other in size and shape, a currentdistribution flowing through the ground electrode GND changes, anddirectivity of an antenna array formed by the power supply elements 121disposed on the flat portion 131 may change. Therefore, by changing theposition at which the cutout portion 136 is formed, it is possible toincrease a degree of freedom in design of the directivity and to achievedesired antenna characteristics.

Note that, in Modification 1, one of the protruding portions 133Acorresponds to the “first protruding portion” of the present disclosure,and the other of the protruding portions 133A corresponds to the “secondprotruding portion” of the present disclosure. In addition, inModification 2, one of the protruding portions 133B and 133C correspondsto the “first protruding portion” of the present disclosure, and theother of the protruding portions 133B and 133C corresponds to the“second protruding portion” of the present disclosure.

(Modifications of Bent Portion: Modification 3, Modification 4)

In the antenna module 100 according to Embodiment 1, the configurationin which the bent portion 135 having a smaller thickness of thedielectric substrate than thicknesses of the flat portion 131 and theflat portion 130 is formed along sides of the inner surfaces (that is,the surfaces facing the mounting substrate 20) of the flat portion 131and the flat portion 130 has been described, but another configurationmay be adopted for the shape and arrangement of the bent portion.

In an antenna device 120C of an antenna module 100C according toModification 3 in FIG. 14 , a bent portion 135A is formed along sides ofouter surfaces of the flat portion 131 and the flat portion 130 (thatis, surfaces that do not face the mounting substrate 20). Note that athickness of the dielectric substrate of the bent portion 135A issmaller than the thicknesses of the flat portion 131 and the flatportion 130. As in the antenna module 100C in FIG. 14 , by forming thebent portion on the sides of the outer surfaces, a curvature radius ofthe bent portion can be increased, and therefore, stress applied to thebent portion can be reduced, and a damage to the bent portion can besuppressed. Further, since a space between the bent portion and themounting substrate can be widened, a damage to the bent portion due tocontact with the mounting substrate can be suppressed.

Note that although not illustrated in the figure, the bent portion maybe formed such that intermediate positions in the thickness directionsof the flat portion 131 and the flat portion 130 are connected to eachother.

Further, when the dielectric substrate 105 forming the respective flatportions and the bent portion has sufficient flexibility, it is optionalto make the thickness of the bent portion thinner than the thicknessesof the flat portion 130 and the flat portion 131.

In an antenna device 120D of an antenna module 100D according toModification 4 illustrated in FIG. 15 , a bent portion 135B has the samethickness as the thicknesses of the flat portion 130 and the flatportion 131. In this case, in a manufacturing process to be describedlater, a process of scraping the dielectric substrate in a portioncorresponding to the bent portion can be omitted, and thus themanufacturing process can be simplified, leading to a reduction in cost.Further, it is possible to ensure durability of the portion of the bentportion 135B.

Note that the configurations of the cutout portions illustrated inModifications 1 and 2 may also be applied to Modifications 3 and 4.

(Modifications of Single Antenna: Modification 5, Modification 6)

In Embodiment 1 and Modifications 1 to 4, a case of the antenna array inwhich the plurality of power supply elements is arranged has beendescribed, however, the features disclosed in Embodiment 1 may beapplicable to an antenna module in which only one power supply elementis disposed.

FIG. 16 is a perspective view of an antenna module 100E according toModification 5. In an antenna device 120E of the antenna module 100E,one power supply element 121 is disposed on the flat portion 131. Onlyone protruding portion 133 is formed in the flat portion 131, and atleast a part of the power supply element 121 is disposed on theprotruding portion 133. Note that the flat portion 131 and the flatportion 130 are connected to each other by the bent portion 135 formedat both end portions in the Y-axis direction of the flat portion 131.

Note that, as long as connection strength between the flat portion 131and the flat portion 130 can be secured, a position where the bentportion 135 is formed may be at one end portion in the Y-axis directionof the flat portion 131, as in an antenna device 120F of an antennamodule 100F according to Modification 6 in FIG. 17 .

Additionally, in each of Modifications in FIG. 16 and FIG. 17 , anexample of a configuration is illustrated in which the power supplyelement 121 is not formed on the flat portion 130, but, as indicated bybroken lines in FIG. 16 and FIG. 17 , the power supply element 121 mayalso be provided on the flat portion 130.

Embodiment 2

In the antenna module according to Embodiment 1, the example of theconfiguration has been described in which the protruding portions areformed in the flat portion (flat portion 131) facing the side surface ofthe mounting substrate.

In Embodiment 2, an example of an antenna module in which protrudingportions are formed in a flat portion (the flat portion 130) facing asurface of a mounting substrate will be described.

FIG. 18 is a perspective view of an antenna module 100G according toEmbodiment 2. With reference to FIG. 18 , the antenna module 100Gincludes an antenna device 120G and the RFIC 110. Similarly to theantenna device 120 according to Embodiment 1, the antenna device 120Gincludes the flat portions 130 and 131 and the bent portion 135 thatconfigure the dielectric substrate 105. A cross-section of thedielectric substrate 105 has a substantially L-shape. The flat portion130 with the Z-axis direction being as a normal direction and the flatportion 131 with the X-axis direction being as a normal direction areconnected to each other by the bent portion 135.

The flat portion 131 has a substantially rectangular shape, and fourpower supply elements 121 are arranged in a row on a surface of the flatportion 131.

The flat portion 130 has a configuration in which a plurality of cutoutportions 137 is formed in the dielectric substrate having asubstantially rectangular shape, and the bent portion 135 is connectedto the cutout portions 137. In portions of the flat portion 130 wherethe cutout portion 137 is not formed, protruding portions 133D thatprotrude in a direction toward the flat portion 131 along the flatportion 130 (that is, in the positive direction of the X-axis) from aboundary portion 134A where the bent portion 135 and the flat portion130 are connected to each other are formed. Protruding ends of theprotruding portions 133D are positioned in the positive direction of theX-axis with respect to a surface on the side of an inner surface (on theside facing the mounting substrate 20) of the flat portion 131.

In the antenna device 120G, four protruding portions 133D are formedcorresponding to four power supply elements 121 arranged on the flatportion 131. Then, one power supply element 121 is arranged for each ofthe protruding portions 133D. Each power supply element 121 on the flatportion 131 is arranged such that at least a part of the power supplyelement 121 overlaps with the protruding portion 13

By configuring the antenna device as described above, the power supplyelement 121 on the flat portion 130 can be arranged in the region AR1 ofthe corner portion of the housing in the comparative example illustratedin FIG. 5 . Therefore, it is possible to effectively utilize a limitedspace in a communication device. Note that, a dimension in the X-axisdirection of the antenna device in the antenna module 100G according toEmbodiment 2 is shorter than that in the antenna device 120 according toEmbodiment 1, but a dimension in the Z-axis direction of the antennadevice in the antenna module 100G is longer than that in the antennadevice 120. The configuration, such as the antenna module 100G iseffective when restriction on a dimension in a thickness direction ofthe communication device 10 is relatively small, and a mounting positionon the mounting substrate 20 is limited. In recent years, an area of abezel portion around a display screen has been narrowed in order toenlarge the screen of a smartphone. In such a case, the configuration,such as the antenna module 100G allows the power supply elements 121 onthe flat portion 130 side to be disposed at an end portion of thehousing as close as possible.

Note that, in Embodiment 2, the flat portion 130 corresponds to the“first flat portion” of the present disclosure, and the flat portion 131corresponds to the “second flat portion” of the present disclosure. InEmbodiment 2, a surface positioned in an outer side portion of the flatportion 131 corresponds to the “first surface” of the presentdisclosure, and a surface positioned in an inner side portion of theflat portion 131 corresponds to the “second surface” of the presentdisclosure. In Embodiment 2, one of the protruding portions 133Dcorresponds to the “first protruding portion” of the present disclosure,and the other protruding portions 133D correspond to the “secondprotruding portion” of the present disclosure.

Also, in Embodiment 2, one of the protruding portions 133D formed in theflat portion 130 corresponds to the “first protruding portion” of thepresent disclosure, and the other protruding portions 133D correspond tothe “second protruding portion” of the present disclosure. Also, inEmbodiment 2, one of the power supply elements 121 arranged on the flatportion 130 corresponds to the “first radiation element” of the presentdisclosure, and the other power supply elements 121 arranged on the flatportion 130 correspond to the “second radiation element” of the presentdisclosure. In Embodiment 2, each of the power supply elements 121arranged on the flat portion 131 corresponds to the “third radiationelement” of the present disclosure.

FIG. 19 is a diagram for describing a slit shape to be formed in amanufacturing process of the antenna module 100G in FIG. 18 . Asillustrated in FIG. 19 , in the dielectric substrate 105, a concaveportion is formed by laser processing or the like in a portion where thebent portion 135 is formed. Then, the slit 150 penetrating in thethickness direction of the dielectric substrate 105 is formed at aboundary portion between the protruding portion 133D and the bentportion 135 in the flat portion 130. By forming such a slit, when thedielectric substrate 105 is bent at the portion of the bent portion 135,it is possible to implement the shape as illustrated in FIG. 18 . Notethat variations of the shape as illustrated in FIG. 8 to FIG. 11 may beapplied to the slit shape.

Embodiment 3

In Embodiment 3, an example of a configuration in which protrudingportions are formed on both flat portions will be described.

FIG. 20 is a perspective view of an antenna module 100H according toEmbodiment 3. In an antenna device 120H of the antenna module 100H, theprotruding portions 133 and 133D are formed on the two flat portions 130and 131, respectively. In the antenna device 120H, the protrudingportion 133D is formed at a position corresponding to the protrudingportion 133, and the bent portion 135 is formed between the cutoutportion 137 of the flat portion 130 and the cutout portion 136 of theflat portion 131. Additionally, the power supply element 121 is disposedat a position where at least a part of the power supply element 121overlaps with the protruding portion on each flat portion.

With such a configuration, it is possible to dispose the antenna devicein a limited space in a communication device. Further, since dimensionsin the X-axis direction and the Z-axis direction of the antenna devicecan be shortened, it is possible to contribute to miniaturization of theantenna module and the communication device. Note that, in Embodiment 3,the flat portion 131 corresponds to the “first flat portion” of thepresent disclosure, and the flat portion 130 corresponds to the “secondflat portion” of the present disclosure. Further, in Embodiment 3, oneof the protruding portions 133 corresponds to the “first protrudingportion” of the present disclosure, and the protruding portions 133Dcorrespond to the “third protruding portion” of the present disclosure.

FIG. 21 is a diagram for describing a slit shape to be formed in amanufacturing process of the antenna module 100H in FIG. 20 . Asillustrated in FIG. 21 , before the dielectric substrate 105 is bent,the protruding portion 133D of the flat portion 130 and the protrudingportion 133 of the flat portion 131 are formed so as to face each other.In addition, the slit 150 that penetrates in the thickness direction ofthe dielectric substrate 105 is formed at the boundary portion betweenthe bent portion 135 and each protruding portion. By forming such aslit, it is possible to implement the shape of the antenna device 120Has illustrated in FIG. 20 when the dielectric substrate 105 is bent atthe portion of the bent portion 135. Note that variations of the shapeas illustrated in FIG. 8 to FIG. 11 may be applied to the slit shape.

Embodiment 4

In Embodiment 3, in the antenna device in which the protruding portionsare formed in the two flat portions, as described above with referenceto FIG. 21 , both the protruding portions are formed so as to face eachother. However, in the configuration according to Embodiment 3, in astate in which the dielectric substrate is bent, a position of aprotruding end of one of the protruding portions does not reach asurface of the other of the protruding portions. Therefore, when theantenna module is incorporated in a housing, a space that cannot beslightly utilized at a corner portion of the housing may remain.

In Embodiment 4, an example of a configuration in which, between twoprotruding portions of one of the flat portions (that is, in a cutoutportion), a protruding portion of the other of the flat portions isformed will be described.

FIG. 22 is a perspective view of an antenna module 100I according toEmbodiment 4. In an antenna device 120I of the antenna module 100I,similarly to the antenna device 120H according to Embodiment 3,protruding portions 133E and 133F are formed in the flat portions 130and 131, respectively. Moreover, each of the protruding portions isformed at such a position that a protruding end of the protrudingportion enters the cutout portion of the other of the flat portions. Inother words, the respective protruding portions are formed such that theprotruding portions 133E and the protruding portions 133F arealternately arranged. The bent portion 135 is formed between theprotruding portion 133E and the protruding portion 133F.

On each flat portion, the power supply element 121 is arranged at aposition where at least a part of the power supply element 121 overlapsthe protruding portion. That is, the power supply elements 121 on theflat portion 130 and the power supply elements 121 on the flat portion131 are arranged in a zigzag shape.

With such a configuration, although a dimension in the Y-axis directionof the antenna module is slightly longer, dimensions in the X-axisdirection and the Z-axis direction can be shortened. Further, it ispossible to incorporate the antenna module into a housing so as not toleave a redundant space in a corner portion of the housing. Therefore,it is possible to effectively utilize a limited space in a communicationdevice and to contribute to miniaturization of the antenna module andthe communication device.

Note that, in Embodiment 4, the flat portion 131 corresponds to the“first flat portion” of the present disclosure, and the flat portion 130corresponds to the “second flat portion” of the present disclosure. InEmbodiment 4, the protruding portion 133E corresponds to the “firstprotruding portion” of the present disclosure, and the protrudingportion 133F corresponds to the “third protruding portion of the presentdisclosure.

FIG. 23 is a diagram for describing a slit shape to be formed in amanufacturing process of the antenna module 100I in FIG. 22 . Asillustrated in FIG. 23 , before the dielectric substrate 105 is bent,the protruding portions 133E on the flat portion 130 and the protrudingportions 133F on the flat portion 131 are formed so as to be alternatelyarranged. At this time, the protruding end of the protruding portion133E is positioned so as to be offset in the positive direction of theX-axis from a position of the protruding end of the protruding portion133F. In addition, the slit 150 that penetrates in the thicknessdirection of the dielectric substrate 105 is formed at the boundaryportion between the bent portion 135 and each protruding portion. Withsuch a configuration, when the dielectric substrate 105 is bent, theprotruding portion 133E can be disposed between the two protrudingportions 133F, and the shape of the antenna device 120I as illustratedin FIG. 22 can be implemented. Note that variations of the shape asillustrated in FIG. 8 to FIG. 11 may be applied to the slit shape.

Embodiment 5

In Embodiments 1 to 4, the example of the antenna module capable ofradiating radio waves in two directions has been described. InEmbodiment 5, an example of an antenna module capable of radiating radiowaves in three directions will be described.

FIG. 24 is a perspective view of an antenna module 100J according toEmbodiment 5. With reference to FIG. 24 , in an antenna device 120J ofthe antenna module 100J, the flat portion 130 with the Z-axis directionbeing as the normal direction has a substantially square flat plateshape, and a flat portion 131A is also formed on the side of a sidealong the X-axis of the flat portion 130, in addition to the flatportion 131 formed on the side of a side along the Y-axis of the flatportion 130. The flat portion 131A has the same shape as that of theflat portion 131, and a plurality of protruding portions 133G is formedtherein. The flat portion 131A is connected to the flat portion 130 by abent portion 135C. On the flat portion 131A, the power supply element121 is disposed such that at least a part thereof overlaps with theprotruding portion 133G. By disposing the antenna device 120J havingsuch a shape at a corner portion where three surfaces of a housingintersect each other, it is possible to radiate radio waves in threedirections that are the X-axis direction, the Y-axis direction, and theZ-axis direction. Then, it is possible to effectively utilize a space ofthe corner portion where three surfaces of the housing intersect eachother.

Note that, in Embodiment 5, the flat portion 131A corresponds to a“third flat portion” of the present disclosure. In addition, inEmbodiment 5, the bent portion 135C corresponds to a “second bentportion” of the present disclosure, and the protruding portion 133Gcorresponds to a “fourth protruding portion” of the present disclosure.In Embodiment 5, each of the power supply elements 121 arranged on theflat portion 131A corresponds to a “fourth radiation element” of thepresent disclosure.

FIG. 25 is a diagram for describing radiation directions of radio waveswhen the antenna modules 100J in FIG. 24 are mounted on the housing 30.In FIG. 25 , the antenna module illustrated in FIG. 24 is disposed ateach of the corner portions at diagonal positions of the housing 30having a substantially rectangular parallelepiped shape. Two antennamodules 100J1 and 100J2 are arranged such that the flat portions 130mutually face opposite directions. Accordingly, radio waves are radiatedfrom the antenna module 100J1 in the positive directions of the X-axis,the Y-axis, and the Z-axis (that is, in X1, Y1, and Z1 directions), andradio waves are radiated from the antenna module 100J2 in the negativedirections of the X-axis, the Y-axis, and the Z-axis (that is, X2, Y2,and Z2 directions). Therefore, with such a communication device, it ispossible to radiate radio waves in all directions.

(Modification)

In the antenna device 120J of the antenna module 100J illustrated inFIG. 24 , the configuration in which radio waves are radiated in thethree directions that are the X-axis direction, the Y-axis direction andthe Z-axis direction has been described, but a configuration may beapplicable in which radio waves are radiated in three directions thatare the positive direction of the X-axis, the negative direction of theX-axis, and the Z-axis direction, as in an antenna device 120J3 of anantenna module 100J3 of FIG. 26 , for example.

In the antenna device 120J3 in FIG. 26 , a flat portion 131J is formedon a side opposite to a side on which the flat portion 131 is formed, ofthe flat portion 130. The flat portion 131J has a shape similar to thatof the flat portion 131, and a plurality of protruding portions 133J areformed thereon. The flat portion 131J is connected to the flat portion130 by a bent portion 135J. Although power supply elements are notillustrated in FIG. 26 because the power supply elements are behind theprotruding portions 133J, the power supply elements are arranged on theflat portion 131J such that at least a part of the power supply elementoverlaps the protruding portion 133J. Radio waves are radiated in thenegative direction of the X-axis from the power supply elements arrangedon the flat portion 131J.

Note that, in FIG. 26 , the example has been described in which the flatportion is formed in the positive direction and the negative directionof the X-axis, but the flat portion may be formed in the positivedirection and the negative direction of the Y-axis.

Embodiment 6

In the above-described embodiments, examples of a so-called single-bandtype antenna device in which only the power supply element is used as aradiation element and radio waves in one frequency band are radiatedfrom each power supply element, and a single-polarization type antennadevice in which radio frequency signals are supplied at one power supplypoint for each power supply element have been described. However, thefeatures of the present disclosure are also applicable to a dual-bandtype antenna device capable of radiating radio waves in two frequencybands from a radiation element, and a dual-polarization type antennadevice capable of radiating radio waves in two polarization directionsfrom a radiation element.

FIG. 27 is a perspective view of an antenna module 100K according toEmbodiment 6. In an antenna device 120K of the antenna module 100Killustrated in FIG. 27 , the dielectric substrate 105 has the same shapeas that according to Embodiment 1, but radiation elements arranged oneach of the flat portions are configured with the power supply elements121 and parasitic elements 122.

The parasitic element 122 has a size larger than that of the powersupply element 121. When viewed from a normal direction of each flatportion, the parasitic element 122 is disposed closer to an inner layerside of the dielectric substrate 105 than the power supply element 121so as to overlap with the power supply element 121. Then, a power supplywiring (not illustrated) penetrates the parasitic element 122 to beconnected to the power supply element 121. By forming the radiationelements in such a configuration, radio waves in mutually differentfrequency bands can be radiated from the power supply element 121 andthe parasitic element 122.

In addition, in each power supply element 121, by connecting the powersupply wiring from the RFIC 110 to two power supply points SP1 and SP2,it is possible to radiate two radio waves having different polarizationdirections from the respective power supply element 121 and parasiticelement 122. For example, radio waves with the X-axis direction being asthe polarization direction and radio waves with the Y-axis directionbeing as the polarization direction are radiated in the Z-axis directionfrom the radiation elements on the flat portion 130. Further, radiowaves with the Y-axis direction being as the polarization direction andradio waves with the Z-axis direction being as the polarizationdirection are radiated in the X-axis direction from the radiationelements on the flat portion 131.

Note that, although the antenna module 100K has been described as anexample of a dual-band and dual-polarization type antenna module, it maybe a dual-band and single-polarization type antenna module, or asingle-band and dual-polarization type antenna module. Further, anaspect of the radiation elements disposed on the flat portion 130 and anaspect of the radiation elements disposed on the flat portion 131 may bedifferent from each other.

As described above, in an antenna module having a dielectric substrateformed in a substantially L-shaped cross-section by bending, at leastone of the flat portions is formed with a protruding portion, and apower supply element is arranged such that at least a part of the powersupply element overlaps with the protruding portion, so that when theantenna module is incorporated in a housing of a communication device,the power supply element can be arranged in a dead space at a cornerportion of the housing. Also, even after the dielectric substrate isbent, a thickness of the protruding portion can be maintained at thesame dimension as a thickness of the flat portion. Therefore, it ispossible to provide a miniaturized antenna module that can be disposedin a limited space in a communication device while suppressing areduction in antenna characteristics.

Embodiment 7

In the above-described embodiments, the configuration in which the RFIC110 is mounted on the mounting substrate 20 and is connected to the flatportion 130 in the dielectric substrate 105 has been described.

In Embodiment 7, a configuration in which an RFIC is disposed on theflat portion 131 side connected to the bent portion 135 will bedescribed.

FIG. 28 is a cross-sectional view of a first example of an antennamodule 100L1 according to Embodiment 7. An antenna device 120L of theantenna module 100L1 is directly connected to the mounting substrate 20with solder bumps 145 interposed therebetween. In the antenna module100L1, an RFIC 110A is disposed on an inner surface of the flat portion131 of the dielectric substrate 105 (that is, on a surface facing themounting substrate 20). In the antenna module 100L1, at least a part ofthe RFIC 110A is disposed on the protruding portion 133 protruding fromthe flat portion 131. Note that the RFIC is not necessarily disposed onthe protruding portion 133, and may be disposed on a portion other thanthe protruding portion 133 in the flat portion 131, as in an RFIC 110Bof an antenna module 100L2 illustrated in FIG. 29 .

The power supply element 121 on the flat portion 130 side is suppliedwith a radio frequency signal from the RFIC 110A (or the RFIC 110B)through a power supply wiring 170A. Further, the power supply element121 on the flat portion 131 side is supplied with a radio frequencysignal through a power supply wiring 171A. Note that, although notillustrated in the figures, a signal is transmitted from the mountingsubstrate 20 to the RFIC 110A, or 110B via the bent portion 135

As described above, since the RFIC is disposed on the flat portion 131side of the dielectric substrate, it is possible to reduce a thicknessof the antenna module in a case where a dimension in a thicknessdirection (Z-axis direction) of a device that houses the antenna moduleis limited.

Embodiment 8

In the above-described embodiments, the configuration in which at leasta part of the power supply element 121 disposed on the flat portion 131side is disposed on the protruding portion 133 of the flat portion 131has been described.

FIG. 30 is a cross-sectional view of an antenna module 100M according toEmbodiment 8. In an antenna device 120M in the antenna module 100M, thepower supply element 121 disposed on the flat portion 131 side isdisposed at a position other than the protruding portion 133 in the flatportion 131.

In the configuration in which the protruding portion is not formed asillustrated in FIG. 5 , since the ground electrode GND is bent,radiation directions of radio waves from the power supply element 121 atthe connection portion between the flat portion 131 # and the bentportion 135 # are inclined toward the positive direction of the Z-axisrather than the positive direction of the X-axis, and antennacharacteristics may be deteriorated. On the other hand, by forming theprotruding portion 133 as in the antenna module 100M in FIG. 30 , it ispossible to secure flatness of the ground electrode GND in a portionwhere the power supply element 121 is disposed, and thus it is possibleto make radiation directions of radio waves from the power supplyelement 121 closer to the positive direction of the X-axis. This makesit possible to improve a gain in the positive direction of the X-axis,and thus it is possible to suppress a decrease in antennacharacteristics.

Embodiment 9

In the above-described embodiments, the configuration has been describedin which the antenna device is formed by bending the dielectricsubstrate itself on which the radiation elements are disposed. InEmbodiment 9, description will be given of a configuration in whichsubstrates on which radiation elements are disposed are separatelymounted on a substrate in which a bent portion is formed to form anantenna device.

FIG. 31 is a cross-sectional view of an antenna module 100N according toEmbodiment 9. An antenna device 120N in the antenna module 100N includesa base substrate 210, a first antenna substrate 220, and a secondantenna substrate 230.

The base substrate 210 includes a dielectric 211 and the groundelectrode GND. The base substrate 210 has a substantially L-shapedcross-sectional shape, and includes a flat portion 130N having a flatplate shape with the Z-axis direction being as a normal direction, aflat portion 131N having a flat plate shape with the X-axis directionbeing as a normal direction, and a bent portion 135N connecting the flatportion 130N and the flat portion 131N.

Similarly to the dielectric substrate 105 described in FIG. 2 ofEmbodiment 1, the flat portion 131N is formed with a protruding portion210A protruding in the Z-axis direction from a boundary portion betweenthe flat portion 131N and the bent portion 135N. The ground electrodeGND is also formed in the protruding portion 210A. The RFIC 110 isconnected to a lower surface side (surface in the negative direction ofthe Z-axis) of the flat portion 130N. The RFIC 110 is mounted on thesurface 21 of the mounting substrate 20 with the solder bumps 140interposed therebetween.

The first antenna substrate 220 is mounted on the flat portion 130N withsolder bumps 145 interposed therebetween. Further, the second antennasubstrate 230 is mounted on the flat portion 131N with solder bumps 146interposed therebetween.

In the first antenna substrate 220, the power supply element 121 isdisposed on a dielectric 221 having a flat plate shape. The power supplyelement 121 on the first antenna substrate 220 is supplied with radiofrequency signals from the RFIC 110 through the power supply wiring170B, thereby radiating radio waves in the Z-axis direction. The powersupply wiring 170B penetrates the flat portion 130N of the basesubstrate 210 from the RFIC 110, passes through the solder bumps 145,and penetrates the dielectric 221 to reach the power supply element 121on the first antenna substrate 220.

In the second antenna substrate 230, the power supply element 121 isdisposed on a dielectric 231 having a flat plate shape. The power supplyelement 121 of the second antenna substrate 230 is supplied with radiofrequency signals from the RFIC 110 through a power supply wiring 171B,and thereby radiates radio waves in the X-axis direction. The powersupply wiring 171B extends from the RFIC 110 into insides of the flatportion 130N and the bent portion 135N of the base substrate 210 or tosurfaces thereof, and reaches the flat portion 131N. Further, the powersupply wiring 171B passes through the solder bumps 146 and penetratesthe dielectric 231 to reach the power supply element 121 on the secondantenna substrate 230. At least a part of the power supply element 121on the second antenna substrate 230 is disposed at a position facing theprotruding portion 210A of the base substrate 210.

As described above, even in the antenna module having the configurationin which the base substrate 210 having the bent portion 135N, and thefirst antenna substrate 220 and the second antenna substrate 230 on eachof which the power supply element 121 is disposed are separately formed,by adopting a structure in which the flat portion 131N protrudes in adirection toward the flat portion 130N with respect to the bent portion135N, the power supply element 121 can be disposed in the region (theregion AR1 in FIG. 5 ) in an inner side portion of the corner portion ofthe housing. This makes it possible to reduce a dimension in the Z-axisdirection of the entire antenna module while maintaining a size of thepower supply element 121, and thus it is possible to provide theminiaturized antenna module that can be disposed in a limited space in acommunication device while suppressing a reduction in antennacharacteristics.

Embodiment 10

In Embodiment 10, a configuration for securing a protruding amount ofthe protruding portion in the flat portion 131 facing a side surface ofa housing will be described.

FIG. 32 is a perspective view of an antenna module 100P according toEmbodiment 10. Further, FIG. 33 is a cross-sectional view of the antennamodule 100P. The antenna module 100P has a configuration in which theantenna module 100A according to Modification 1 illustrated in FIG. 12is further modified. Specifically, in an antenna device 120P of theantenna module 100P, cutout portions 180 are formed at an end portion ofthe flat portion 130 of the dielectric substrate 105, and a dimension (alength in the Z-axis direction) of each of protruding portions 133P ofthe flat portion 131 corresponding to the cutout portions 180 is longerthan that in the case of Modification 1.

In other words, in a case of the antenna module 100P, in the processillustrated in FIG. 7B of the manufacturing process described withreference to FIGS. 7A-7D, a part of the slit 150 is formed so as toextend to a region of the flat portion 130. As a result, it is possibleto secure the protruding amount of the protruding portion 133P of theflat portion 131, and as illustrated in FIG. 33 , it is possible to makea tip end of the protruding portion 133P higher than an upper surface ofthe dielectric of the flat portion 130.

Note that the tip end of the protruding portion is not necessarilypositioned above the flat portion 130. That is, as in an antenna module100P1 in FIG. 34 , a tip end of a protruding portion 133P1 may bepositioned lower than an upper surface of the flat portion 130, or a tipend of a protruding portion 133P2 may be aligned with the upper surfaceof the flat portion 130 as in an antenna module 100P2 of FIG. 35 .

Embodiment 11

In Embodiment 11, a configuration in which a shape of a connectionportion between the flat portion 130 and the bent portion 135 is made acircular arc shape to suppress a reduction in flexibility will bedescribed.

FIG. 36 is a perspective view of an antenna module 100Q according toEmbodiment 11. In the antenna module 100Q, a connection portion betweenthe flat portion 130 and the bent portion 135 in the flat portion 130 ofthe antenna module having a substantially L-shape is cut in a circulararc shape to form a concave portion 181.

In the manufacturing process described with reference to FIGS. 7A-7D,when the bent portion 135 is formed by reducing the thickness of thedielectric, or when the laser processing for forming the slits 150 isperformed, a part that is not processed may remain on the side of thebent portion 135 due to a factor, such as a positional shift, and thedielectric may be thicker than a desired thickness. When such a partthat is not processed remains, flexibility of the part decreases, andthere is a possibility that the power supply wiring is disconnected dueto stress concentration that occurs due to the decrease in flexibility.

In the antenna module 100Q, by forming the concave portions 181 having acircular arc shape in the connection portion between the flat portion130 and the bent portion 135, it is possible to suppress the occurrenceof the part that is not processed on the side of the bent portion 135.This makes it possible to suppress a decrease in flexibility of the bentportion 135, and thus it is possible to suppress the disconnection ofthe power supply wiring at the boundary portion between the flat portion130 and the bent portion 135.

Embodiment 12

In Embodiment 12, a configuration in which an end surface of each flatportion of the dielectric substrate 105 has a tapered shape will bedescribed.

As described in the manufacturing method of the antenna module in FIGS.7A-7D, when the flat portion 130 and the flat portion 131 of thedielectric substrate 105 are formed, laser processing may be used insome cases. When an opening portion is formed from an upper surfacetoward a lower surface of a substrate by using the laser processing, adielectric is removed by using the laser processing also in a peripheralportion of a desired opening position in order to reliably form theopening portion on the upper surface side, but as for on the lowersurface side, the processing is ended at the time when the openingportion penetrates the lower surface, so as a result, a size of theopening portion on the upper surface side tends to be larger than a sizeof the opening portion on the lower surface side. That is, an endsurface from which the dielectric is removed does not have a right anglewith respect to a main surface of the dielectric substrate, and may havea tapered shape in many cases. More specifically, a removal width of thesurface of the dielectric substrate on the side close to an irradiationsource of the laser tends to be wider than a removal width of thesurface on the side farther from the irradiation source. Therefore, thetapered shape of the end surface is different between a case where thelaser is irradiated from the front surface side of the dielectricsubstrate and a case where the laser is irradiated from the rear surfaceside of the dielectric substrate.

FIG. 37 is a cross-sectional view of a first example of an antennamodule 100R according to Embodiment 12. The antenna module 100R is anexample of the case where the laser is irradiated from the side of thefront surface (that is, a surface on which the power supply element 121is disposed) when the dielectric substrate 105 is formed. Therefore, inthe antenna module 100R, a dimension of the surface on which the powersupply element 121 is disposed is narrower than a dimension of thesurface on which the ground electrode GND is disposed.

When the end surface of the flat portion of the dielectric substrate 105has a tapered shape as illustrated in FIG. 37 , some of electric linesof force from the power supply element 121 to the ground electrode GNDpass through the air outside the dielectric substrate 105, and thereforean effective dielectric constant between the power supply element 121and the ground electrode GND decreases. Accordingly, it is possible toimprove antenna characteristics.

On the other hand, an antenna module 100S of a second exampleillustrated in FIG. 38 is an example of the case where the laser isirradiated from the side of the rear surface (that is, the surface onwhich the ground electrode GND is disposed) when the dielectricsubstrate 105 is formed. Therefore, in the antenna module 100S, adimension of the surface on which the power supply element 121 isdisposed is larger than a dimension of the surface on which the groundelectrode GND is disposed.

In the case of the second example in FIG. 38 , when the bent portion 135is bent, it is possible to prevent a protruding portion 133S and theflat portion 130 from being brought into contact with each other.

Embodiment 13

In each of the above-described embodiments, description has been givenof a configuration in which, in the dielectric substrate, the flatportion 131 connected through the bent portion from the flat portion 130that is one flat portion of the dielectric substrate is bent from theflat portion 130 toward the mounting substrate 20 side. In Embodiment13, a configuration in which the bent portion is bent from the flatportion 130 to the side opposite to the mounting substrate 20 will bedescribed.

FIG. 39 is a cross-sectional view of an antenna module 100T according toEmbodiment 13. The antenna module 100T has a configuration in which abent portion 135T is bent in the positive direction of the Z-axis fromthe flat portion 130, and the flat portion 131 is connected to the bentportion 135T. That is, the flat portion 131 has a shape protruding inthe positive direction of the Z-axis direction with respect to the flatportion 130. Then, the protruding portion 133 is formed in the negativedirection of the Z-axis from a connection portion between the bentportion 135T and the flat portion 131. In such a configuration, whenthere is a margin in a space on an upper side (the positive direction ofthe Z axis) of the flat portion 130, it is possible to dispose the powersupply element 121 in a region of a corner portion of a housing.

Note that, as illustrated in an antenna module 100U in FIG. 40 , aconfiguration may be applicable in which in a case where a bent portion135U is formed on the side of a surface of the flat portion 130 on whichthe power supply element is disposed, the bent portion 135U is bent tothe side opposite to the mounting substrate 20.

Embodiment 14

In the above-described embodiments, a case where a bending angle of thebent portion is 90° has been described, but the bending angle may belarger than 90°.

For example, as in an antenna module 100V in FIG. 41 , a bent portion135V may be bent by about 180° (e.g., 90° or more and 185° or less) inthe positive direction of the Z-axis from the flat portion 130.Alternatively, as in an antenna module 100W in FIG. 42 , a bent portion135W may be bent by about 180° (e.g., 90° or more and 185° or less) inthe negative direction of the Z-axis from the flat portion 130.

Also, in such a configuration, it is possible to effectively utilize alimited space in a housing.

Note that, in FIG. 41 and FIG. 42 , the case where the bent portion isbent by about 180° (e.g., 90° or more and 185° or less) has beendescribed as an example, but the bending angle of the bent portion canbe appropriately selected within a range equal to or larger than 90° andequal to or smaller than 180°.

Embodiment 15

In each antenna module of the above-described embodiments, theconfiguration has been described in which radio waves are radiated inthe X-axis direction and/or the Y-axis direction in addition to adirection perpendicular to the surface of the mounting substrate (thatis, the Z-axis direction). In Embodiment 15, a configuration in whichradio waves are radiated in two directions that are the X-axis directionand the Y-axis direction will be described.

FIG. 43 is a perspective view of an antenna device 120X of an antennamodule 100X according to Embodiment 15. In the antenna device 120X, adielectric substrate 105X includes a flat portion 131X1 with the X-axisdirection being as a normal direction, a flat portion 131X2 with theY-axis direction being as a normal direction, and a bent portion 135X.The flat portion 131X2 is connected to the flat portion 131X1 by thebent portion 135X. A protruding portion 133X is formed in the positivedirection of the X-axis from a connection portion between the flatportion 131X2 and the bent portion 135X. Such an antenna device 120X is,for example, disposed at a corner portion of a side surface of themounting substrate.

A plurality of power supply elements 121 is arranged in each of the flatportions 131X1 and 131X2. Therefore, radio waves are radiated from theantenna module 100X in two directions that are the positive direction ofthe X-axis and the positive direction of the Y-axis. In addition, on theflat portion 131X2, at least a part of the power supply element 121disposed at a position closest to the flat portion 131X1 is disposed soas to overlap with the protruding portion 133X. With such aconfiguration, it is possible to utilize a space of a corner portionformed by adjacent side surfaces of a housing.

Note that, in the above-described embodiments, the configuration inwhich the radiation elements are disposed on the flat portion has beendescribed, but, in addition to these, other radiation elements may beformed on a front surface and/or a rear surface of the bent portion. Inthis case, not only a patch antenna having a flat plate shape, but alsoa linear antenna, such as a monopole antenna and a dipole antenna may beformed as the radiation element. Furthermore, the features of each ofthe above-described embodiments can be combined as appropriate within arange in which no contradiction occurs.

It should be considered that the embodiments disclosed herein areillustrative in all respects and are not restrictive. The scope of thepresent disclosure is indicated by the claims rather than thedescription of the above-described embodiments, and it is intended toinclude all modifications within the meaning and scope equivalent to theclaims.

REFERENCE SIGNS LIST

-   -   10 COMMUNICATION DEVICE    -   20 MOUNTING SUBSTRATE    -   21 SURFACE    -   22 SIDE SURFACE    -   30 HOUSING    -   100, 100A TO 100N, 100P TO 100X ANTENNA MODULE    -   105, 105X DIELECTRIC SUBSTRATE    -   110, 110A, 110B RFIC    -   111A to 111D, 113A TO 113D, 117 SWITCH    -   112AR TO 112DR LOW-NOISE AMPLIFIER    -   112AT TO 112DT POWER AMPLIFIER    -   114A TO 114D ATTENUATOR    -   115A TO 115D PHASE SHIFTER    -   116 SIGNAL MULTIPLEXER/DEMULTIPLEXER    -   118 MIXER    -   119 AMPLIFICATION CIRCUIT    -   120, 120A TO 120N, 120P TO 120X ANTENNA DEVICE    -   121 POWER SUPPLY ELEMENT    -   122 PARASITIC ELEMENT    -   130, 130N, 131, 131A, 131J, 131N, 131X FLAT PORTION    -   133, 133A TO 133G, 133J, 133P TO 133S, 133X, 210A PROTRUDING        PORTION    -   134, 134A BOUNDARY PORTION    -   135, 135A TO 135C, 135J, 135N, 135T TO 135X BENT PORTION    -   136, 137, 180 CUTOUT PORTION    -   140, 145, 146 SOLDER BUMP    -   150, 150A, 150B SLIT    -   152, 181, 195 CONCAVE PORTION    -   155 CORNER PORTION    -   170, 170A, 170B, 171, 171A, 171B POWER SUPPLY WIRING    -   190 ELECTRODE    -   200 BBIC    -   210 BASE SUBSTRATE    -   220, 230 ANTENNA SUBSTRATE    -   211, 221, 231 DIELECTRIC    -   ED1, ED2 END POINT    -   GND GROUND ELECTRODE    -   SP, SP1, SP2 POWER SUPPLY POINT    -   ST, ST1, ST2 START POINT

The invention claimed is:
 1. An antenna module comprising: a dielectricsubstrate; and a first radiation element on the dielectric substrate,wherein the dielectric substrate includes a first flat portion and asecond flat portion, and a first bent portion connecting the first flatportion and the second flat portion, the first flat portion has a firstprotruding portion partially protruding toward the second flat portion,the first bent portion is provided at a position where the firstprotruding portion is not provided in the first flat portion, and atleast a part of the first radiation element is on the first protrudingportion.
 2. The antenna module according to claim 1, wherein the firstflat portion and the second flat portion have mutually different normaldirections.
 3. The antenna module according to claim 1, wherein thefirst protruding portion partially protrudes toward the second flatportion along the first flat portion from a boundary portion between thefirst bent portion and the first flat portion.
 4. The antenna moduleaccording to claim 1, wherein the first flat portion and the first bentportion are connected to each other at the position where the firstprotruding portion is not provided in the first flat portion.
 5. Theantenna module according to claim 3, wherein the second flat portionincludes a first surface, and a second surface positioned opposite tothe first surface and closer to the first flat portion than the firstsurface, and the first protruding portion extends from the boundaryportion between the first bent portion and the first flat portion to aposition exceeding the second surface.
 6. The antenna module accordingto claim 1, wherein a thickness of the first bent portion is smallerthan a thickness of the first flat portion.
 7. The antenna moduleaccording to claim 1, wherein a thickness of the first flat portion isequal to a thickness of the second flat portion.
 8. The antenna moduleaccording to claim 3, further comprising: a power supply wiringconfigured to transmit a radio frequency signal to the first radiationelement, wherein the power supply wiring is connected to a power supplypoint of the first radiation element, and the boundary portion betweenthe first bent portion and the first flat portion is positioned in adirection toward the first protruding portion with respect to the powersupply point.
 9. The antenna module according to claim 3, furthercomprising: a second radiation element on the first flat portion. 10.The antenna module according to claim 9, wherein the first flat portionfurther includes a second protruding portion partially protruding in adirection toward the second flat portion along the first flat portionfrom the boundary portion between the first bent portion and the firstflat portion, and at least a part of the second radiation element is onthe second protruding portion.
 11. The antenna module according to claim9, wherein the first radiation element and the second radiation elementare on the first protruding portion.
 12. The antenna module according toclaim 1, further comprising: a third radiation element on the secondflat portion.
 13. The antenna module according to claim 12, wherein thesecond flat portion includes a third protruding portion partiallyprotruding in a direction toward the first flat portion along the secondflat portion from a boundary portion between the first bent portion andthe second flat portion, the second flat portion and the first bentportion are connected to each other at a position where the thirdprotruding portion is not provided in the second flat portion, and atleast a part of the third radiation element is on the third protrudingportion.
 14. The antenna module according to claim 2, wherein thedielectric substrate further includes a third flat portion having anormal direction different from the normal directions of the first flatportion and the second flat portion, and a second bent portionconnecting the second flat portion and the third flat portion, the thirdflat portion includes a fourth protruding portion partially protrudingin a direction toward the second flat portion along the third flatportion from a boundary portion between the second bent portion and thethird flat portion, and the third flat portion and the second bentportion are connected to each other at a position where the fourthprotruding portion is not provided in the third flat portion, theantenna module further comprising: a fourth radiation element on thethird flat portion.
 15. The antenna module according to claim 1, furthercomprising: a power supply circuit configured to supply a radiofrequency signal to each radiation element.
 16. A communication devicecomprising: the antenna module according to claim
 1. 17. An antennamodule comprising: a dielectric substrate; and a radiation element onthe dielectric substrate, wherein the dielectric substrate includes afirst flat portion and a second flat portion, and a first bent portionconnecting the first flat portion and the second flat portion, the firstflat portion has a first protruding portion partially protruding towardthe second flat portion, the first bent portion is arranged at aposition where the first protruding portion is not provided in the firstflat portion, and the radiation element is at a position other than thefirst protruding portion in the first flat portion.
 18. The antennamodule according to claim 17, wherein the first flat portion and thesecond flat portion have mutually different normal directions.
 19. Theantenna module according to claim 17, wherein the first protrudingportion partially protrudes toward the second flat portion along thefirst flat portion from a boundary portion between the first bentportion and the first flat portion.
 20. The antenna module according toclaim 17, further comprising: a power supply circuit configured tosupply a radio frequency signal to each radiation element.